CT EVALUATION OF AMYLOIDOSIS - SPECTRUM OF DISEASE

Amyloidosis is a rare systemic disease caused by extracellular deposit ion of an insoluble protein. Although it is usually seen in a systemic form, 10%-20% of cases can be localized. Systemic amyloidosis is subc lassified into an idiopathic primary form and a secondary or reactive form. Patients with primary amyloidosis have no underlying condition o r disease. Men are affected more than women, and the mean age at prese ntation is 55-60 years. Some causes of secondary amyloidosis are multi ple myeloma (10%-15%), rheumatoid arthritis (20%-25%), tuberculosis (5 0%), or familial Mediterranean fever (26%-40%). Radiographic studies o f 90 patients with biopsy-proved primary or secondary amyloidosis were reviewed. Computed tomographic (CT) scans demonstrated a wide spectru m of disease in the cardiothoracic, gastrointestinal, genitourinary, a nd musculoskeletal systems. Amyloid deposition simulated both inflamma tory and neoplastic conditions. Amorphous or irregular calcifications were occasionally identified within the amyloid deposit. Definitive di agnosis requires biopsy confirmation, as CT findings are nonspecific.